Cleaning black tank.

The ice method is helpful but only on a reasonably clean tank. The other part the video does not include is the big jug o dawn. Again a reasonably clean tank, 50 to 100 lbs of ice and a large bottle of dawn will clean the tank, and in some cases may revive those non functioning sensors. Once you let solids build up and dry it's hot water and patience.

I will use a dollar store dish soap several times a month after a dump and rinse, minty fresh ...no but better none the less